Easy disassembling in cleaning and filling up water.With two functions of hanging or attaching to tank wall by suction cup.Acrylic material provides clear and easy bubble reading.CO2 pipe fasten screw node prevents bursting out of the CO2 pipe.Loose the cap (upper part) and fill the reservoir with clear water then fasten the cap firmly.Secure the CO2 pipe according to the inlet and outlet indication marks with the screw node.By changing the clip on the cap to select attaching of hanging or by suction cup.